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Discussion Starter · #1 ·
can anyone help me out, since i put straight pipes on and cut out the cats and mufflers, ive lost alot of torque, i thought, doin such a thing would give me gains,, do i need a tune, is it cus of loss of back pressure, is there a way i can regain my torque and keep my sound of straight pipes,,, any knowledge is appreciated
 

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can anyone help me out, since i put straight pipes on and cut out the cats and mufflers, ive lost alot of torque......
Doubt it.

Some will say that you lost torque do to having less back-pressure in the exhaust system.

I'm one to that that the lack of exhaust components make the car's exhaust louder and leads you to believe that you're pulling more RPMs than before to get the same amount of power.

Also....since you have a '96, what did you do about the O2 sensors that plug into the cats? If you simply 'removed' them from your exhaust system, that can cause you issues, too.

Whatever the case, re-instaliing your components (or at least the cats) will solve the problem.

KW
 

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Doubt it.

Some will say that you lost torque do to having less back-pressure in the exhaust system.

I'm one to that that the lack of exhaust components make the car's exhaust louder and leads you to believe that you're pulling more RPMs than before to get the same amount of power.

Also....since you have a '96, what did you do about the O2 sensors that plug into the cats? If you simply 'removed' them from your exhaust system, that can cause you issues, too.

Whatever the case, re-instaliing your components (or at least the cats) will solve the problem.

KW
Umm...the rear O2 sensors don't do ANYTHING regarding how the engine runs...all they do is turn on the check engine light by throwing a code that essentially says "hey, I'm not spewing clean emissions".

Less back pressure from the exhaust generally means the torque happens at higher RPM...which generally means more horsepower. So long as the engine is able to rev high enough to take advantage of it without damage.
 

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You didn't lose "torqe", you moved it to a higher RPM.

An X pipe will likely correct it, and eliminate much of the ******* pickup truck sound too.
 

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Discussion Starter · #6 ·
ya i have a x pipe also, sounds better then cars without for sure, thinkin bout adding some glaspacks, to see if tht helps any,
 

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My bad.

Guess I shouldn't have paid any attention to this article :( --->> http://www.asashop.org/autoinc/dec2002/mech.htm

KW
A lot of that article is a great introductory explanation to how the sensors work and what the PCM does with the data from them...but ALL of the engine control (on every make/model vehicle I've toyed with) is based entirely on the PRE cat O2 sensors...the rear sensors function the same way, and are often the same part number sensors as the fronts for that respective platform, but the rears are really only there as monitors...the PCM runs the engine off the front sensors, and based on what those front sensors are doing, it knows what the rear sensors should be showing for readings, which is a result of proper functioning catalytic converters...if the readings aren't right, the PCM will throw emissions codes or sensor codes (the readings could be bad due to actual emissions or due to bad rear oxygen sensors), but those specific codes will have absolutely NO effect on engine operation.
 
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